Process of manufacturing artificial silk and other products from nitrocellulose



Patented Nov. 17, 1925.

UNITED STATES 1,562,076 PATENT OFFICE.

EMILE BINDSCHEDLEB, LANSDOWNE, PENNSYLVANIA, ASSIGNOR TO TUBIZE ARTIFICIAL SILK COMPANY OF AMERICA, A CORPORATION OF. DELAWARE.

PROCESS OF MANUFACTURING ARTIFICIAL SILK AND OTHER PRODUCTS FROM V N ITRO CELLULOSE.

No Drawing.

To all whom it may concern:

' Be it known that I, EMILE Binoscin-tninzn, a citizen of the Republic of Switzerland, and resident of Lansdowne. county of Delaware, State of Pennsylvania, have invented ess in which-nitrocellulose hydrate of to watercontentfidissolved in a mixture of alcohol and ether, is exuded through an orifice, to give form to a product and to coagulate the exuded material by extraction of the solvents, and the object of my invention is to provide an improved method of coagulation whereby a softer product is obtained and whereby also, especially in the case of artificial silk filaments, a finer denier,

g as well as. a softer thread, can be produced.

It hasbeen-proposed to coagulate the exuded filamentsof nitrocellulose collodion by passing them through a bath of dilute alcohol. In. order to get clear and lustrous products, I found'that it is necessary to use alcohol of at least 40%. I have'also discovered that while alcohol of a certain strength acts as a rapid coagulating agent, the rate of coagulation can be retarded, by mixing with the alcohol, a certain percentage of glycerine, and that the product is softer and improved by' the impregnation with glycerine. The slower coagulation occurrin in my new setting bath, makes it poss'ib e toproduce very fine threads. \Vhen the filaments come out through orifices of a usual diameter into a mixture of ethylalcohol and glycerine, they are in a semicoagulated state, which allows them to be drawn out into .threads of a very low denier by drawing them through the bath at a speed greater than 'its rate of exudation through the formed orifices.

The alcohols well adapted for use in my coagulation bath are the aliphatic monohydroxy alcohols, and of these, ethyl-alcohol is best fitted for the purpose.

The proportion of alcohol and glycerine in the bath can vary within wide limits,

from 40% alcohol and 60% glycerine to 75% alcohol and 25% glycerine. Good re sults are, for instance, obtained by a mix- Application filed May 31, 1924. Serial No. 716,?69.

ture of equal parts of ethyl-alcohol and glycerine, kept at a temperature of .from 20 to 35 C. It is self evident that the solvents can be easily and economically recovered from the spinning bath by simple distillation and both solvents and, spinning bath re-used indefinitely.

In order to complete the coagulation, the threads pass afterwards through dilute alcohol of 40 to 60% and finally they are wound on bobbins, rotating in water, to remove and recover the dilute alcohol. The threads are then twisted, reeled and denitrated according to Well known methods.

It is, however, not essential to use the second bath as set forth, as it is also possible. to wind the threads coming out from the alcohol-glycerine bath directly on bobbins rotating in water.

Having now described my invention, What I claim as new and desire to secure by Letters Patent, is:

1. Process of manufacturing nitrocellulose products from nitrocellulose hydrate, dissolved in a mixture of alcohol and ether, in which the collodion is exuded through orifices and the formed product drawn away and coagulated in a bath composed of a mixture-of an aliphatic monohydroxy alcohol and glycerine and drawing the product through said bath at a speed greater than its rate of exudation.

2. Process of manufacturing nitrocellulose products l'rom nitrocellulose hydrate, dissolved in a mixture of alcohol and ether, in which the collodion is exuded through an orifice and the formed product drawn awa and coagulated in a bath consistin of ethy alcohol mixed with glycerine and drawing the product through said bath at a speed greater than its exudation.

3. Process of manufacturing nitrocellulose products from nitrocellulose hydrate, dissolved in a mixture of alcohol and ether in which the collodion is exuded through an orifice and the formed product drawn away in which the collodion is exuded through an orifice and the formed product drawn away and coagulated in a bath consisting of a mixture of an aliphatic monohydroxy alcohol and glycerine. Y

5. Process of manufacturing nitrocellulose articles from nitrocellulose hydrate dissolved in a mixture of alcohol and ether, in which the collodion is exuded through an orifice and the formed product drawn away. and coagulated in a bath consisting of a mixture of ethyl-alcohol and glycerine.

v 6. Process of manufacturing artificial silk filaments from nitrocellulose hydrate, dissolved in a mixture of alcohol and ether, in which the collodion is exuded through an orifice and the formed filaments drawn away into a bath consisting of an aliphatic monohydroxy alcohol with glycerine and 7 Process of manufacturing artificial silk filaments from nitrocellulose hydrate, dissolved in a mixture of alcohol and Ether, in which the collodion is exuded through an orifice andthe formed filaments drawn away into a bath consisting of ethyl-alcohol mixed with glycerine and drawing the filaments through said bath at a speed exceeding its rate of exudation so as to produce filaments v parts ethyl-alcohol and 25 to 60 "parts glyc erine, 'and drawing the filaments through said bath at a speed exceeding its rate of exudation, so as to. produce filaments of finer denier.

EMILE. BINDSCHEDLER. 

